Chinese scientist who sparked controversy over DNA claims ‘needs time to provide evidence’
Chinese scientist Han Chunyu says he needs more time to provide evidence to support his controversial claims about a new gene-editing tool, which have been questioned by his peers on the mainland and abroad.
“I beg everyone to be a bit more patient. I [insist] what I said before [is true], but there will be new information soon,” the associate professor of biology told the Science and Technology Daily, a newspaper run by the Ministry of Science and Technology, on Tuesday evening.
More Chinese researchers have broken their silence and joined the call for an investigation into Han’s experiment, which was initially hailed as a breakthrough in engineering human and animal genes.
Two influential mainland life scientists, Professor Rao Yi of Peking University, and Professor Shao Feng, deputy director of the National Institute of Biological Sciences in Beijing, who initially supported Han’s claims, published an open letter on Tuesday evening demanding that Han’s university investigated his experiment.
Their letter followed an open petition signed on Monday by about a dozen Chinese laboratories, which questioned Han’s findings and called for a “thorough investigation by an independent third party”.
In May, Han’s team at Hebei University of Science and Technology claimed they had developed NgAgo, a powerful technology that would allow biologists to manipulate the genes of humans and other living species with unprecedented simplicity and accuracy. But since then many laboratories in China and around the world have failed to replicate the results.
“This is a tipping-point for China’s academic environment, which requires the serious attention of the whole scientific community,” Shao was quoted as saying by the Science and Technology Daily.
“We have tried to communicate with Sun Hexu, president of Hebei University of Science and Technology, but with little effect, so [we] chose to publish this letter.”
Han said on Monday that at least five laboratories had repeated his experiments and he would release the names of these laboratories if his critics on the mainland went public with their accusations.
But on Tuesday evening he told the Science and Technology Daily that it was still “inconvenient” to name the laboratories.
Some researchers said the NgAgo study could become the Chinese version of the infamous Stap scandal in Japan.
In 2014, a research team led by scientist Haruko Obokata reported that they been able to produce “stimulus-triggered acquisition of pluripotency [Stap] cells”, which allowed the easy generation of almost any tissues in human body. But the study turned out to be a fraud.
Obokata also claimed that some laboratories had repeated her experiment, but did not provide their names.
The NgAgo technology uses an ancient bacteria to manipulate the genes of living species, including humans, at will.
Han admitted that the technology still needed improvements and the poor results at other laboratories could have been caused by some unknown mechanisms associated with Ago, the ancient bacteria.
“Ago existed widely in the microscopic world, and its defence mechanisms, many of which remained unknown, could be the main reason behind the poor replication results,” he was quoted as saying on Tuesday evening by the newspaper.
“[I] hope the scientists who went public against me can solve the problem together with us,” Han added.